678 to them. These devices include the nets built by many trichopteran larvae, fringes of hairs on the forelegs and/or mandibles of some larval Plecoptera, the fans on the premandibles of black fly larvae, and the sticky strings of saliva produced by the chironomid Rheotanytarsus (Hynes, 1970a,b).

An important factor in the distribution of aquatic insects, and one that is related to the extent of water movement, is the substratum. Many species of stream insects are characteristically associated with particular types of substratum. For some insects the significance of this association is easily understood. For example, water pennies [larvae of Psephenidae (Coleoptera)], found in fast-moving waters, require largish rocks to which they can become attached. Similarly, larval Blepharoceridae (Diptera) need smooth rocks, not covered with silt or algal growth, to which to attach their suckers. And some Leuctridae (Plecoptera) require gravel of the correct texture in which to burrow.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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